Systems for producing and/or coating granular fertilizers can involve multiple unit operations, including fluidized bed heating and cooling, rotary drums, size screeners and various forms of materials transport. Mechanisms such as bucket elevators may be utilized to transfer heated substrates from a fluidized bed heater into a separate rotary coating vessel. Following coating, products may then be transferred into a separate fluidized bed cooler to further set the coating agents and prepare the product for further handling and storage. After being cooled, the coated vessels may be transferred to a final scalping screener. As such, the granular material is required to be transferred multiple times through the coating process which may lead to process inefficiency and losses in quality. The separate operations can also increase the number of open transfer points in the system. In addition, additional expenses may be required to properly provide adequate floor space and height in order to accommodate the system.
Therefore, a need exists for an efficient and effective system to produce and coat granular fertilizers.